Mitochondria - the 'brain power' behind cell division

Washington, April 27 : A study on yeast cells has found that mitochondria, the fuel of a cell, is the "driver" for cell division.

This discovery could play a big role in finding cures for many human diseases, biochemists at the Texas AgriLife Research said.

The biochemists studied yeast cells and found that mitochondria, which generates 90 percent of the cell's energy, can be the deciding factor - the "brain power" - behind how fast cells divide.

"The finding changes the traditional view of the mitochondrion from an 'energy depot' at the service of its larger cellular host to a 'command center' that directs cell division," said Drs. Michael Polymenis and Mary Bryk.

The researchers used regular baker's yeast - commonly used in breads, wine and beer making - because many of the yeast cell's processes are similar to those in human cells, according to Bryk.

"From unicellular yeast to complex mammals, the process is the same. The job of a cell is to divide and grow. Metabolism takes in 'food' and turns it into fuel and building blocks for DNA replication and gene expression," she added.

But when these processes falter, diseases can result. Too much cell division too quickly, for example, is typical of cancerous cells, Polymenis pointed out. Conversely, poor metabolism - stemming from mitochondrial deficiencies - is at the root of damage to various organs such as the brain, heart, skeletal muscles and liver.

"All of the body processes that require a lot of energy are impacted by this. In fact, at least 1 in every 4,000 people worldwide suffer from mitochondrial deficiencies that result in problems with normal development, motor control, vision, hearing, or liver and kidney function," Bryk said.

On the other hand, there are times when speeding cell division might be useful as with wound healing and plant or crop production, she noted.

"If we can understand the basic pathway that regulates cell division, we can think of ways to tweak the different steps in that path with therapeutics to help people who have problems with these high-energy organs," she said.

Polymenis said the research showed that when a yeast cell's mitochondria decided to "turn on the switch," the cell's nucleus - which carries most of the genetic material - received the message and cell division began.

"So now we need to connect that link," Polymenis said.

"We need to understand how and when the message is sent. If we know how the message is sent from the mitochondria, we might be able to control it," he added.

The finding was published in open-access journal Public Library of Science-Genetics.